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Privacy-Preserving Key-Updatable Public Key Encryption with Keyword Search Supporting Ciphertext Sharing Function

  • Wang, Fen;Lu, Yang;Wang, Zhongqi;Tian, Jinmei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.1
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    • pp.266-286
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    • 2022
  • Public key encryption with keyword search (PEKS) allows a user to make search on ciphertexts without disclosing the information of encrypted messages and keywords. In practice, cryptographic operations often occur on insecure devices or mobile devices. But, these devices face the risk of being lost or stolen. Therefore, the secret keys stored on these devices are likely to be exposed. To handle the key exposure problem in PEKS, the notion of key-updatable PEKS (KU-PEKS) was proposed recently. In KU-PEKS, the users' keys can be updated as the system runs. Nevertheless, the existing KU-PEKS framework has some weaknesses. Firstly, it can't update the keyword ciphertexts on the storage server without leaking keyword information. Secondly, it needs to send the search tokens to the storage server by secure channels. Thirdly, it does not consider the search token security. In this work, a new PEKS framework named key-updatable and ciphertext-sharable PEKS (KU-CS-PEKS) is devised. This novel framework effectively overcomes the weaknesses in KU-PEKS and has the ciphertext sharing function which is not supported by KU-PEKS. The security notions for KU-CS-PEKS are formally defined and then a concrete KU-CS-PEKS scheme is proposed. The security proofs demonstrate that the KU-CS-PEKS scheme guarantees both the keyword ciphertext privacy and the search token privacy. The experimental results and comparisons bear out that the proposed scheme is practicable.

Feature Analysis of Metadata Schemas for Records Management and Archives from the Viewpoint of Records Lifecycle (기록 생애주기 관점에서 본 기록관리 메타데이터 표준의 특징 분석)

  • Baek, Jae-Eun;Sugimoto, Shigeo
    • Journal of Korean Society of Archives and Records Management
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    • v.10 no.2
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    • pp.75-99
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    • 2010
  • Digital resources are widely used in our modern society. However, we are facing fundamental problems to maintain and preserve digital resources over time. Several standard methods for preserving digital resources have been developed and are in use. It is widely recognized that metadata is one of the most important components for digital archiving and preservation. There are many metadata standards for archiving and preservation of digital resources, where each standard has its own feature in accordance with its primary application. This means that each schema has to be appropriately selected and tailored in accordance with a particular application. And, in some cases, those schemas are combined in a larger frame work and container metadata such as the DCMI application framework and METS. There are many metadata standards for archives of digital resources. We used the following metadata standards in this study for the feature analysis me metadata standards - AGLS Metadata which is defined to improve search of both digital resources and non-digital resources, ISAD(G) which is a commonly used standard for archives, EAD which is well used for digital archives, OAIS which defines a metadata framework for preserving digital objects, and PREMIS which is designed primarily for preservation of digital resources. In addition, we extracted attributes from the decision tree defined for digital preservation process by Digital Preservation Coalition (DPC) and compared the set of attributes with these metadata standards. This paper shows the features of these metadata standards obtained through the feature analysis based on the records lifecycle model. The features are shown in a single frame work which makes it easy to relate the tasks in the lifecycle to metadata elements of these standards. As a result of the detailed analysis of the metadata elements, we clarified the features of the standards from the viewpoint of relationships between the elements and the lifecycle stages. Mapping between metadata schemas is often required in the long-term preservation process because different schemes are used in the records lifecycle. Therefore, it is crucial to build a unified framework to enhance interoperability of these schemes. This study presents a basis for the interoperability of different metadata schemas used in digital archiving and preservation.

Characteristics of Environmental Solar Ultraviolet Irradiance

  • Sasaki, Masako;Oyanagi, Takehiko;Takeshita, Shu
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.154-157
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    • 2002
  • Direct, continuous, and accurate measurements of solar ultraviolet irradiance (290-400 nm: UVR) have been carried out since 1990, by using both band-spectral ultraviolet-B (290-320 nm: UV-B) and ultraviolet-A (320-400 nm: UV-A) radiometers at Tokai University in Hiratsuka, Japan (35$^{\circ}$N, 139$^{\circ}$E). From our observations, the following findings are provided: 1) an increasing trend in solar UV -B from Oct. 1990 to Sept. 2000; 2) a regional comparison of solar UVR in Japan; 3) the distinct characteristics of UV-B and UV-A irradiance, such as diffuse property, daily and seasonal variation; and 4) human body protection against solar UVR. An increasing 10-year trend in global solar UV - B in Hiratsuka corresponded to a decrease in the total ozone amount measured at Tsukuba (36$^{\circ}$N, 140$^{\circ}$E), giving supportive evidence for a direct link between these two parameters. Furthermore, a strong correlation was found between solar UV-B and total ozone amount from results of UVR measurements at four Tokai University monitoring stations dispersed throughout Japan. Additional results revealed different diffuse properties in global solar UV and in global solar total (300-3000 nm: Total) irradiances. For example, in the global UVR, the diffuse component was dominant: about 80 % independent of weather, with more than 60 % of global UV-B, and more than 50% of global UV-A with even a cloudless clear sky. On the other hand, the portion of the diffuse in the global total irradiance was very low, less than 10 % on a cloudless clear day. Daily and seasonal variations of UV -B and UV -A irradiances were found to be quite different, because of the marked dependence of UV -B irradiance on the atmospheric ozone amount. Moreover, UV -B irradiance showed large daily and seasonal variations: the ratio between maximum and minimum irradiances was more than 5. In contrast, the variation in UV-A was small: the ratio between maximum and minimum was less than 2. Three important facts are proposed concerning solar UVR protection of the human body: 1) the personal minimal erythema dose (MED); 2) gender based difference in MED values; and 3) proper colors for UVR protective clothing.

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AKARI FAR-INFRARED ALL-SKY SURVEY MAPS

  • Doi, Yasuo;Komugi, Shinya;Kawada, Mitsunobu;Takita, Satoshi;Arimatsu, Ko;Ikeda, Norio;Kato, Daisuke;Kitamura, Yoshimi;Nakagawa, Takao;Ootsubo, Takafumi;Morishima, Takahiro;Hattori, Makoto;Tanaka, Masahiro;White, Glenn J.;Etxaluze, Mireya;Shibai, Hiroshi
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.111-116
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    • 2012
  • Far-infrared observations provide crucial data for the investigation and characterisation of the properties of dusty material in the Interstellar Medium (ISM), since most of its energy is emitted between ~ 100 and $200{\mu}m$. We present the first all-sky image from a sensitive all-sky survey using the Japanese AKARI satellite, in the wavelength range $50-180{\mu}m$. Covering > 99% of the sky in four photometric bands with four filters centred at $65{\mu}m$, $90{\mu}m$, $140{\mu}m$, and $160{\mu}m$ wavelengths, this achieved spatial resolutions from 1 to 2 arcmin and a detection limit of < 10 MJy $sr^{-1}$, with absolute and relative photometric accuracies of < 20%. All-sky images of the Galactic dust continuum emission enable astronomers to map the large-scale distribution of the diffuse ISM cirrus, to study its thermal dust temperature, emissivity and column density, and to measure the interaction of the Galactic radiation field and embedded objects with the surrounding ISM. In addition to the point source population of stars, protostars, star-forming regions, and galaxies, the high Galactic latitude sky is shown to be covered with a diffuse filamentary-web of dusty emission that traces the potential sites of high latitude star formation. We show that the temperature of dust particles in thermal equilibrium with the ambient interstellar radiation field can be estimated by using $90{\mu}m$, $140{\mu}m$, and $160{\mu}m$ data. The FIR AKARI full-sky maps provide a rich new data set within which astronomers can investigate the distribution of interstellar matter throughout our Galaxy, and beyond.

Peroxiredoxin System of Aspergillus nidulans Resists Inactivation by High Concentration of Hydrogen Peroxide-Mediated Oxidative Stress

  • Xia, Yang;Yu, Haijun;Zhou, Zhemin;Takaya, Naoki;Zhou, Shengmin;Wang, Ping
    • Journal of Microbiology and Biotechnology
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    • v.28 no.1
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    • pp.145-156
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    • 2018
  • Most eukaryotic peroxiredoxins (Prxs) are readily inactivated by a high concentration of hydrogen peroxide ($H_2O_2$) during catalysis owing to their "GGLG" and "YF" motifs. However, such oxidative stress sensitive motifs were not found in the previously identified filamentous fungal Prxs. Additionally, the information on filamentous fungal Prxs is limited and fragmentary. Herein, we cloned and gained insight into Aspergillus nidulans Prx (An.PrxA) in the aspects of protein properties, catalysis characteristics, and especially $H_2O_2$ tolerability. Our results indicated that An.PrxA belongs to the newly defined family of typical 2-Cys Prxs with a marked characteristic that the "resolving" cysteine ($C_R$) is invertedly located preceding the "peroxidatic" cysteine ($C_P$) in amino acid sequences. The inverted arrangement of $C_R$ and $C_P$ can only be found among some yeast, bacterial, and filamentous fungal deduced Prxs. The most surprising characteristic of An.PrxA is its extraordinary ability to resist inactivation by extremely high concentrations of $H_2O_2$, even that approaching 600 mM. By screening the $H_2O_2$-inactivation effects on the components of Prx systems, including Trx, Trx reductase (TrxR), and Prx, we ultimately determined that it is the robust filamentous fungal TrxR rather than Trx and Prx that is responsible for the extreme $H_2O_2$ tolerence of the An.PrxA system. This is the first investigation on the effect of the electron donor partner in the $H_2O_2$ tolerability of the Prx system.

Secular change of physical growth in Korean children and youth between 1999 and 2005 (아동 및 청소년 신체발육의 단기적 시대변화)

  • Kim, Myung;Kim, Hye-Kyeong;Matsuura, Yoshiyuki
    • Korean Journal of Health Education and Promotion
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    • v.24 no.5
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    • pp.69-85
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    • 2007
  • Purpose: The purpose of this study is to clarify the traits of differences supposed as secular differences in physical growth between samples of children and youth in 1999 and 2005, and to identify the need of children and youth for health promotion. Methods: Two samples of different cohort were selected. The first one was consisted of 231 boys and 346 girls in 1999. And the other was consisted of 171 boys and 400 girls in 2005. Then the longitudinal growth distance data were collected from their cumulative health examination records. Results: The 2005 were larger in growth distances of stature, body weight, sitting height, and chest girth a at all ages from 6 to 16 in both boys and girls, so it could be concluded that a certain positive shift in growth process appeared in such a short duration. The 2005 were larger in growth velocity before peak age and also after peak age in body weight, but only in the term after peak age significant secular differences were found in stature for both sexes. As far as the growth distance concerned, the 2005 boys were ahead of the 1999 boys from 0.28-1.02 years and the 2005 girls from 0.32 to 0.81 years. In growth distance. Only in peak velocity, significant secular change was recognized in both sexes, any positive evidences of appearance of secular change were not found in peal age. In such derived physical indices as BMI, body weight index, sitting height index, and chest girth index, obvious evidences of secular change appearance were found.

The Reception of 'Bauhaus Photographies' and Propaganda in Modern Japan: Rethinking of Yamawaki Iwao's Photomontage (근대일본의 '바우하우스 사진' 수용과 국가선전: 야마와키 이와오의 '포토몽타주'에 대한 재조명을 통하여)

  • Suh, Hee-Jung
    • The Journal of Art Theory & Practice
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    • no.9
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    • pp.59-91
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    • 2010
  • The Bauhaus educational method gave the strong influences on Modern Japanese art and design education. In the 1920s and 1930s, Japan allied with Germany and Italy politically and tried to receive German system to be modernized. The reception of the Bauhaus and Moholy-Nagy's photographic theory was one of those activities at that time. Japanese intellectual class went to the Bauhaus and studied there; Ishimoto Kikuchi, Nakata Sadanosuke, Mijutani Takehiko, Yamawaki Iwao and Yamawaki Michiko(Yamawaki Iwao's wife). Especially, Yamawaki Iwao studied about the architecture at the Bauhaus, but his interest moved toward the photography and the photomontage based on Moholy-Nagy's theory. He studied at the photography workshop of the Bauhaus presented by Peterhans irregularly. Even though Yamawaki Iwao was an architect, he wanted to be admitted as an expert for the photomontage that he particularly studied at the Bauahus as a Bauhaus member. He had presented many articles about the photomontage at the photography magazines in Japan in order to introduce it to Japan since he returned in 1933. Thus, Yamawaki Iwao is the important person when we look back the Modern Japanese design and art history. In Japan, the art and design systems are managed by the Bauhaus educational system until now, and it has become a kind of cultural legacy in Modern Japan; The university of Tama and The university of Tsukuba are the representative educational systems which are based on the Bauhaus legacy. However, Yamawaki Iwao had been concealed as a photographer in Japanese design and photography history until the retrospective discuss named by 'Bauhaus syashin(Bauhaus Photographies)' at the photography magazine, Deja-vu in 1995 and the retrospective exhibition titled as 'Bauhaus syashin(bauahustofografie)' in 1997. This study rethinks of Yamawaki Iwao's historical position while looking at the term as 'Bauhaus Syashin(Bauhaus Photographies)' used in Japan. It is very important to bear in mind Moholy-Nagy's wide variety of approaches to photography at the Bauhaus, but it is impossible to name it 'Bauhaus style'. 'Bauhaus style' is the international style in architecture, but that was never a Bauhaus style in photography. Eugene J. Prakapas indicated that the vague term of 'Bauhaus Photographies' in his article in 1985 as well. This study considers the historical background for the mistake of the term of 'Bauhaus Syashin(Bauhaus Photographies)' in Modern Japanese history, while looking at Yamawaki Iwao's photomontage faintly entering on the historical stage again to discuss the reception of the photomontage from him. In particular, Some of Yamawaki Iwao's photomontage presented as the wall photography in Japan during the Second World War, that was related to the propaganda of Japanese government. It had not been known well in the modern Japanese art and design history because it was related to a declaration of the Second World War by Japan. However, the historical position of his photomontage is very important for Japanese history when we rethink of the reception of the Bauhaus and Moholy-Nagys' photographic theory to build up the Japanese modern history. In the result, this study wants to discuss that the mistake of the term of 'Bauhaus syashin(Bauhaus Photographies)' in Japan is related to the interpretation for the the historical position for Yamawaki Iwao's photomontage in the reception of Bauhaus and Moholy-Nagy's photography in Japan.

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Comparison of plantar pressure and COP parameters in three types of arch support insole during stair descent in elderly with flatfoot (편평족 노인의 계단 하강 보행 시 아치 지지형 인솔 종류에 따른 족저압력 및 균형성 평가)

  • Han, Ki-Hoon;Bae, Kang-Ho;Jung, Ha-gon;Ha, Min-Sung;Choi, Do-Yeol;Lee, Joong-Sook;Yang, Jeong-Ok
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.3
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    • pp.948-955
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    • 2018
  • The purpose of this study was to compare plantar pressure and COP parameters in three types of arch support insole during stair descent in elderly with flatfoot. A total of 14 women elderly were recruited for this study. Pedar-X was used to obtain plantar pressure(peak pressure, mean pressure, and contact area) and COP(distance, displacement, excursion) parameters. One-way ANOVAs were used to compare peak pressure, mean pressure, and contact area, distance of COP, displacement of COP, and excursion of COP. Among the plantar pressure parameters, significant(p<0.05) differences were observed in M3 for the peak pressure, M2, M3, and M4 for the mean pressure, and M2, M3, and M6 for the contact area. Among the COP parameters, distances of COP both in the mediolateral and anteroposterior axes revealed significant(p<0.05) differences. The larger peak pressure values of type A and B insoles were observed as compared to normal insole. The larger peak pressure and shorter COP distance values of type A and B insoles were observed as compared to normal insole.

A Study on the Establishment & Functional Characteristics of Health Facilities for the Aged in Japan

  • Kim, Tae Il;Yoshida, Tomo Hiko
    • Architectural research
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    • v.8 no.1
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    • pp.1-7
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    • 2006
  • Various housing measures are needed for the rapidly aging society of Korea. In particular, the welfare policy for the elderly has changed towards the community care. Taking this fact into consideration, it is necessary to have the establishment of a system that offers the elderly appropriate welfare services at their appropriate residence (ageing in place) for the effectiveness of the community care. In this aspect, there are a number of implications to Korea to study merits and demerits of the Health Facilities for the Aged (HFA) in Japan. The society of Japan has been rapidly aging since 1970, and Korea is to face the same situation. As for the data of this study, a total of 2,393 facilities (as of November 1999) mentioned in the annual report of the Japanese Ministry of Health, Labor and Welfare were classified based on types of their establishment: (1) free-standing structures (603 facilities); (2) annexes to hospitals (981 facilities); (3) annexes to welfare facilities (511 facilities); and (4) annexes to clinics (298 facilities). Next, 239 facilities were selected through taking a sample of 10 percent from each type of the HFA mentioned above. This was done through the random sampling method with the computer program of MS EXCEL. The Implications of the results of analyses are as follows. First, most of the health facilities were planned with the scale that was larger than the scale of standard special nursing homes in terms of the total floor area. Precise equations that were to obtain precise results of the scale of the HFA and the appropriate number of residents were obtained through the method of the regression analysis. Korea and Japan have similarities in terms of culture, society and family relations; however, the two countries also have differences in terms of the application of laws on the establishment of houses, hospitals, and welfare facilities. As for planning the scale of the HFA, the realities of Korea should be considered. Second, as for the functional aspect of the HFA with a condition of returning home, the place before and after the HFA showed the pattern of 'from a residential place to a residential place' and 'from a hospital to a hospital.' This reveals a close correlation with the types of the HFAs and operational ways of the facilities. Its cause is considered to be the aspect of the operation and management of the HFA rather than the aspect of its function of providing services in association with medical and health facilities. Therefore, when intermediate welfare facilities are considered in Korea, it is strongly advised to consider the problem of annexes to other facilities and efficiency of sharing of the facilities in terms of its operation and management.

In vivo metabolism of carbofuran in resistant and susceptible brown planthoppers, Nilaparvata lugens $St{\aa}l$ (저항성 및 감수성 벼멸구 체내에서의 카보후란 대사)

  • Yoo, Jai-Ki;Ahn, Yong-Joon;Shono, Toshio;Lee, Si-Woo
    • The Korean Journal of Pesticide Science
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    • v.2 no.2
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    • pp.75-82
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    • 1998
  • This study was conducted to find out the biochemical or metabolic resistance mechanism of brown planthopper (BPH) to carbofuran. Differences between resistant ($LD_{50};\;20.3{\mu}g/g$) and susceptible strains($LD_{50};\;0.3{\mu}g/g$) were shown. The amounts of carbofuran metabolite, benzofuranol, and the origin, not developed by Thin Layer Chromatography, were much more in the susceptible strain. But the mother compound, carbofuran, was much more in the resistant strain. The tendencies of metabolism one and three hours after treatment were similar in both strains except for the amounts of metabolites described above. From the study, it is supposed that hydrolytic enzyme, esterase, changes its role from cleaving the esteric bond of carbofuran to making conjugates with carbofuran. This seems to be the main resistance mechanism of BPH to carbofuran. Oxidase and transferase may play little or no role in resistance mechanism. Oxidative and transferring enzymes gave no effects on the metabolism of carbofuran in the resistant strain compared with the susceptible strain.

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